The present invention relates to a fixture for aligning and clamping a workpiece, in particular a pack of printed circuit boards, on a machine tool.
As is known, a piece to be worked on a machine tool must be positioned accurately on the worktable of the machine, which is achieved by means of locating elements normally provided on the workpiece. In the case of packs of printed circuit boards, each pack is provided with a pair of pins projecting from one face of the pack, and which are fitted inside seats on an aligning and clamping fixture.
In one known fixture for packs of printed circuit boards, one of the pins is brought in correspondence with a pair of bars, one of which is moved parallel to itself by a complex mechanism; and the fixture also comprises an aligning or locating member in which the other pin is located and then positioned and clamped by an independent actuator by means of a further mechanism.
The above fixture has several drawbacks. In particular, it is complicated, bulky and fairly expensive, on account of the numerous component parts of the two mechanisms. Moreover, requiring two actuators necessarily operated in a predetermined sequence, the fixture is relatively slow-operating and subject to mistiming.